What is the type hint for a function

Question

Is it just callable? In the meantime I have been using function as my IDE regards callable as a bool.

def func(a: int, b: str, callback: ???)

Answer 1

Yes, typing.Callable is the right hint for a callback.

Also see the Callable section of PEP 484:

Frameworks expecting callback functions of specific signatures might be type hinted using Callable[[Arg1Type, Arg2Type], ReturnType].